Upon measuring a dynamic change rate in force, pressure, torque, velocity, acceleration, position, deflection, impact, weight, mass, degree of vacuum, turning moment, vibration, noise and the like through distortion (stress), generally, a dynamic quantity sensor device constructed using pressure resistance effect material has been widely used.
The pressure resistance effect refers to a phenomenon that electric resistance of material changes when compression stress, tensile stress, shearing stress, normal hydrostatic pressure stress is applied.
By applying a dynamic quantity to a pressure sensing body made of such a material through an insulation body from outside, electric resistance of the pressure sensing body is changed and by detecting this change, its dynamic quantity is measured.
However, a conventionally known dynamic quantity sensor device is so structured that an external dynamic quantity to be measured is applied to a dynamic quantity sensor device through an appropriate insulation body.
For the reason, when a high load is measured by applying a high pressure or the like as a dynamic quantity, a balance of load application upon an internal pressure sensing body is bad although this is not always true when the dynamic quantity is small. Therefore, an accurate dynamic quantity measurement is difficult and insulation of the pressure sensing body is also difficult to secure.
Further, installation of such a device onto a measuring system or the like so as to secure insulation for the pressure sensing body was troublesome.
Thus, a dynamic quantity sensor device capable of measuring the dynamic quantity at a high precision and easily securing insulation of the pressure sensing body has been demanded.
Further, as a composite material which constitutes a load sensor for measuring uniaxial load, an acceleration sensor device or a pressure sensor device, semiconductor silicone monocrystal, silicon carbide and the like, which are materials having a pressure resistance effect, are used conventionally.
Further, as a pressure resistance effect material, La1−xSrxMnO3 particles and the like, which is perovskite type complex oxide, have been known.
The pressure resistance effect mentioned here refers to a phenomenon that electric resistance of material changes when compression stress, tensile stress, shearing stress, normal hydrostatic pressure stress is applied.
These conventional pressure resistance effect materials have such a disadvantage that its mechanical strength is weak. Thus, when these conventional pressure resistance effect materials are used as a sensor material, a structure for protecting the sensor material is necessary and therefore, the structure of the entire sensor becomes complicated.
For the reason, developments of the load sensor device, acceleration sensor device and pressure sensor device whose pressure sensing body has a high strength and a simple structure of dynamic quantity sensor device has been demanded.